Drawing board



Dec. 4, 1951 SEFERQW 2,577,159

DRAWING BOARD Filed March 17, 1949 r [I II II IIIHI ll IHI ll ll'l II 0 I; I a P HIIIILHHIIIIIIHIIIIIUll I N V EN TOR; Pfi er Se/H0117 HTTGF/VEY Patented Dec. 4, 1951 OFFICE DRAWING BOARD Eeter-Seferow, New York, N. Y.

Application March. 17, 1949; Serial No. 8 1,863

The present invention relates to drawing boards, and more particularly to drawing boards having means for moving and retaining a straight-edge in parallel relation to the hori zontal edges ofthe drawing surface:

Drawing boards, generally used by'draft'smen, are provided with a straight-edge having pulleys, or the like, at the. ends, which are guided by a cord, or cable,. at each side of the board tomain tain the straight-edge in parallel'relation. One of the difficulties of such" drawing boards is that the cords; due to their flexibility; stretch upon frequent use of'the board,whereby the straightedge acquires free play' and no longer is accu rately maintained in its parallel relation to the horizontal. This condition is further exaggerated' where the cords are stretched orare loosened unevenly thereby tending to position the straight-edge at an angle to the horizontal edges of the drawing surface. leads to the making of inaccurate drawings.

The present invention aims to overcome the foregoing difiiculty by providing a drawing board wherein the straight-edgeis positively maintained in its parallel relation by intermeshing means associated with the board and the straight-edge.

Accordingly, an object of the present invention is to. provide an improved drawing board having a straight-edge combined" therewith which is simple and economical in construction and can be readily operated without danger. of disturbing its alignment.

Another. object is to provide" a drawing board of the foregoing character wherein the straightedge may be pushed into desired approximate positions and operating means may be utilized for positioning the same more accurately.

Another object is to provide such operating means which are simple andpractical and can be manipulated in a convenient manner.

Another object is to' provide a drawing board of the foregoing character wherein a brake is associated with the operating: means which serves toret'ain the straight-edgein desiredipositionsof adjustment...

A. further obj ect is .to .provide hinge means for mounting the straighteedge between the moving and retaining means which facilitate placing the work between the straight-edge and thedraw.-

ing surface. 7

Other and further objects will be obvious upon an understanding of the illustrative embodiment about to be described, or:- will be indicatedinthe appended-claims, and variousradvantagesnoti-re- This difficulty ferred' to herein will. occur to one skilled in: the art upon employment of; the invention in practice.

A preferred embodiment of the-invention has been chosen for purposes of.- illustration. anddescription and is shown in: the accompanying drawing,- forming a part of the specification, wherein Figure 1 is a fragmentary plan: view: of: a draw ing board in accordance with: the: invention.

. Figure 2- is: asectional view taken along the line 22 on Figure 1.

Figure 3 isa sectional view taken substantially along the line 3'-3- on Figure 1.

Referring to the drawingin detail; there is shown a drawing board. generally comprising" a base ('0, a frame member H, at each side of the base, a top l2, a drawing surface [4" on the top,- a straight-edge ['5' above the drawing surface; and means in accordance with the presentinvention for moving and maintaining the straight-edge in parallel relation with the horizontal" edges of the board, which means will" be describedin detail hereinafter.

The frame members are in the. form of a chartnel having a lower flange 20', an upper flangewzl, and a web 22, with a longitudinally extending slot 24,. connecting. the. flanges. The. lower flanges are mounted on; and secured.-v to" the. base l0 adj acenttheside edges thereof and theiupper. flanges support the top member- [2 and are secured thereto.

One of the: flanges; of each-channel; preferably the lower flange 20 as shown; has a gear rack 25 mounted and secured thereon which extends substantially from; endto end of the side members and length of the slot 24. A gear 26 is mounted on each gear rack and a rotatable shaft 21 has both gears secured thereto for rotation therewith. The ends of .theshaft freely extend through the slots and outwardly beyond the side frame members II for thepurpose about to be described.-

A plate 30 is provided at theouter si'deof each frame member which-has a bearing aperture 3|- through which the. ends of the shaft 21 extend; The straight-edge l5 has its ends connected to the plates 30 to provide a movable carriage' structure consisting of'the: gears 26, the shaft, the plates 30 and the straight-edge: I5 which structure is in positive meshing relationxwith the gear racks25 and. hence-ois'locked against-being moved out of. parallel alignment. Preferably; the: ends: or. the; straight-edge: I15 are connected to the platesziillzibyratdoubleihinge vided with a manually engageable knob 40 to facilitate rotating of the shaft 27 whereby the gears 26 and gear racks cooperate to effect movement of the straight-edge acrossthe drawing surface. 9

In order to retain the straight-edge in desired.

positions of adjustment while working on the board, a brake is associated with one of the plates and one of the knobs 49. This brake comprises an annular member 4| threaded on the shank of the knob, a friction disc 42 adjacent the plate 30, and a coil spring 44 disposed about the threaded shank and having its endsengaging the member 4| and the disc 42. The member 4| may be adjusted on the shank of the knob to vary the compression of the spring and its braking effect. In this manner, movement of the shaft 27 with respect to the plate 30 is prevented unless sufficient force is applied to rotate the knobs or push the straight-edge to overcome the friction established by the spring. From the foregoing description, it will be seen that the present invention provides an improved drawing board having means for moving and maintaining the straight-edge in its desired alignment. The parts of the board are readily manufactured and assembled and can readily withstand such rough usage to which they may normally be subjected.

While the intermeshing means have been illustrated and described specifically in connection with gears on a shaft and gear racks, it wil1 be appreciated that other equivalent mechanism may be utilized, such mechanism consisting of interconnected rotatable members cooperating with fixed track members.

As various changes may be made in the form, construction and arrangement of the parts here: in, without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matters are to be interpreted as illustrative and not in any limiting sense.

I claim: 7 1. A drawing board comprising a base, a channel member having the lower flange thereof mounted on said base and extending along each side thereof, said channel member having a lengthwise extending slot in the web thereof, a gear rack mounted on a flange of each channel member, a drawing surface mounted on the upper flanges of said channel members, a straight edge member above said drawing surface 'having its ends adjacent the sides of .said drawing sur.-'.-: face, a gear for each of said gear racks, a rotat able shaft having said gears mounted thereon for rotation therewith, and having itsends extending outwardly through said slots, a bearing member adjacent the web of each of said channel members mounted on said shaft adjacent each end thGIGOflhinge means for connecting the ends of said straight-edge member to. said bearing members, and a-knob at oneiend of said shaft for effecting rotationthreofi .2;

2. A drawing board comprising a base, a channel member having the lower flange thereof mounted on said base and extending along each side thereof, said channel member having a. lengthwise extending slot in the web thereof, a gear rack mounted on a flange of each channel member, a drawing surface mounted on the upper flanges of said channel members, a straightedge member above said drawing surface having its ends adjacent the sides of said drawing surface, a gear for each of said gear racks, a rotatable shaft having said gears mounted thereon for rotation therewith and having its ends extending outwardly through said slots, a bearing member adjacent the web of each of said channel members mounted on said shaft adjacent each end thereof, means for connecting the ends of said straight-edge member to said bearing members, a knob at one end of said shaft for effecting rotation thereof, and a brake including a spring coiled about said shaft between said knob and one of said bearing members for retarding rotation of said shaft with respect to said bearing member to thereby retain said straight-edge in a predetermined position with respect to said drawing surface.

3. A drawing board comprising a base, a channel member having the lower flange thereof mounted on said base and extending along each side thereof, said channel member having a lengthwise extending slot in the web thereof, a gear rack mounted on a flange of each channel member, a drawing surface mounted on the upper flanges of said channel members, a straightedge member above said drawing surface having its ends adjacent the sides of said drawing surface, a gear for each of said gear racks, a rotatable shaft having said gears mounted thereon fcr rotation therewith, and having its ends extending outwardly through said slots, a bearing member adjacent the web of each of said chan nel members mounted on said shaft adjacent each end thereof, hinge means for connecting the ends of said straight-edge member to said bearing members, a knob at each end of said shaft for effecting rotation thereof, and a brake including a spring coiled about said shaft between one of said knobs and one of said bearing members for retarding rotation of said shaft with respect to said bearing member to thereby retain said straight-edge in a predetermined position with respect to said drawing surface.

4. A drawing board in accordance with claim 3 in which said hinge means includes a double hinge at each end of the straight-edge member.

' PETER SEFEROW.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 647,677 Leighton Apr. 17, 1900 1,288,871 Goodspeed -1 Dec. 24, 1918 1,322,592 McTaggart Nov. 25, 1919 1,441,939 Muller Jan. 9, 1923 1,610,547 Burda Dec. 14, 1926 2,002,676 Owens May 28,v 1935 2,420,090 Nelson May 6, 1947 FOREIGN PATENTS Number Country. Date 22,803 .1 GreatBritain Oct. 27, 1908 71 751.028 France Apr. 11,1924: 

